GRANVILLE STP, VILLAGE OF
NPDES ID: IL0022331
E — SNC: Effluent violation (monthly average limit)
The facility discharged more of a pollutant than its permit allows, based on a monthly average.
This quarter: 13 effluent violations, 12 permit schedule violations.
Mentions
Granville treatment plant exceeds discharge limit
Granville STP in LaSalle County is in significant non-compliance for exceeding its monthly average discharge limit for at least one pollutant. Facilities violating monthly average limits are releasing treated wastewater above permitted concentrations and must correct the exceedance immediately; a violation that persists signals inadequate treatment capacity or process control.
Keep readingViolations
July 31, 2026
Nitrogen, ammonia total [as N]
21% over limit
Discharged 12.64389989 kg/d against a permitted limit of 10.44199991 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
14% over limit
Discharged 5.67045995 kg/d against a permitted limit of 4.99399996 kg/d (WKLY AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
197% over limit
Discharged 5.67045995 kg/d against a permitted limit of 1.90679998 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Coliform, fecal general
Limit violation
Discharged 0 MPN/100mL against a permitted limit of 400 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
268% over limit
Discharged 9.21 mg/L against a permitted limit of 2.5 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
499% over limit
Discharged 5.992 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (6 months ago)
Last confirmed
October 29, 2026 (yesterday)